1. Field of the Invention
The present invention relates to an auto-focus single-lens reflex camera which has an auto-focusing device, and which is capable of being switched over to a manual focusing operation after focusing has been performed automatically.
2. Description of the Prior Art
In a known auto-focus single-lens reflex camera having an auto-focusing function, the operation of the camera is switched over from an auto-focusing mode to a manual focusing mode or from a manual focusing mode to an auto-focusing mode by operating a switch-over button or the like. This type of camera is therefore equipped with a manual switch or the like, and is inconvenient in use. When it is detected that distance-measuring is impossible in the auto-focusing mode and the AF motor is stopped, a button or the like must be operated to switch over the operation mode to the manual focusing mode. Further, when shooting photographs in the auto-focusing mode, it is impossible to focus the focusing lens on a subject located outside the distance measuring zone at the center of a view finder without changing the picture composition. In such a case, the operation mode must be switched over to a manual focusing mode by operating a switch-over button or the like so as to correct the focusing. Such an operation is very troublesome, and the driving mechanism of the lens may be damaged if the manual focusing member provided on a focusing lens is forcibly and carelessly moved before the operation mode is switched over to the manual focusing mode.
These disadvantages of the prior art are overcome by the present invention, which provides an auto-focusing device which allows the focusing mode of a camera to be switched over from the auto-focusing mode to the manual focusing mode in a simplified manner when the distance from a subject cannot be measured in the auto-focusing mode or when it is desired to adjust a focused position intentionally. This is accomplished by automatically conducting in the auto-focusing mode the switching over of the operation mode between the auto-focusing and manual focusing modes in the auto-focusing mode by controlling its operation within the camera body.